Stem Cell Transplantation After Reduced-Dose Chemotherapy for Patients With Sickle Cell Disease or Thalassemia

Hemoglobinopathies, such as sickle cell disease and thalassemia major, are genetic diseases associated with significant morbidity and premature death. Allogeneic bone marrow transplantation (BMT) is the only potential cure for severe hemoglobinopathies. Typical regimens have used high doses of chemotherapy or chemo-radiotherapy to ablate recipient hematopoiesis and to prevent graft rejection. The widespread use of this treatment has been limited by toxicity, risk of end-organ damage, and donor availability. This study will use a nonmyeloablative regimen of fludarabine and busulfan to attempt to generate consistent engraftment with donor hematopoietic stem cells in patients with severe hemoglobinopathy. G-CSF mobilization of the donor's peripheral blood white blood cells will precede donor apheresis. A nonmyeloablative conditioning regimen of fludarabine and busulfan will be administered to patients prior to allogeneic peripheral blood stem cell infusions. FK506 and prednisone will be administered for graft versus host disease (GVHD) prophylaxis. Patients will be evaluated for engraftment, donor: host hematopoietic chimerism, toxicity, and hemoglobinopathy.